The vice president's latest remarks on a potential 2016 bid came Thursday night, questioning whether he has the "emotional energy" to run so soon after his eldest son, Beau, died from brain cancer in May.

For all the chatter and predictions of the past month that Biden was eagerly readying a run, the vice president has put forth a different face when he has spoken about a campaign. And it's one of a grieving father, a not-yet-healed family and someone who certainly doesn't sound mentally prepared for the emotional rigors of the campaign trail.

"I will be straightforward with you. The most relevant factor in my decision is whether my family and I have the emotional energy to run," Biden said in Atlanta, where he was speaking on the Iran nuclear deal. He was asked after his remarks about his intentions for a possible campaign. "Some might think that is not appropriate. But unless I can go to my party and the American people and say that I am able to devote my whole heart and my whole soul to this endeavor, it would not be appropriate."

Biden, 72, said there were other concerns, too — whether he can ramp up a competitive organization with such a late start, wooing donors and staff and building infrastructure in early states. But those weren't driving his decision.

"That's not the factor," a visibly drained Biden told the crowd in a Georgia synagogue. "The factor is: Can I do it? Can my family undertake what is an arduous commitment that we'd be proud to undertake in ordinary circumstances? The honest-to-God answer is I just don't know."

Biden is no stranger to tragedy, and he has soldiered on in the face of it before. Shortly after his election to the Senate in 1972, his wife and daughter were killed in a car accident and his two sons — Beau and Hunter — were badly injured. He had to be convinced to even take the oath of office, and he did, in the hospital beside his children.

The vice president referenced that first deep loss on Thursday night, but said he had learned "there's no way to put a timetable on" recovery from the scars.

"If I can reach that conclusion that we can do it in a fashion that would still make it viable, I would not hesitate to do it," Biden continued. "But I have to be honest with you, and everyone who's come to me, I can't look you straight in the eye and say, 'Now I know I can do that.' That's as honest as I can be."

This was an even more honest and raw assessment than Democratic insiders heard last week from Biden. On a closed conference call with the Democratic National Committee to sell the Iran deal, Biden again opened up about his presidential decision-making — and didn't sound any closer to pulling the trigger.

"If I were to announce to run," Biden said, "I have to be able to commit to all of you that I would be able to give it my whole heart and my whole soul, and right now, both are pretty well banged up. ... I've given this a lot of thought and dealing internally with the family on how we do this."

Multiple reports have said that Beau encouraged him to run before he died, and while the idea of a presidential campaign at that point may have seemed feasible, it's clear the elder Biden is still not ready — and there's no sign when he will be.

Unfortunately for the vice president, the clock is ticking. He initially said he would make an announcement by the end of the summer. The unofficial end is this Monday on Labor Day, but technically by that deadline he has until Sept. 22.

But it's actual deadlines that are important instead of symbolic ones. The first Democratic debate on Oct. 13 is on the horizon, and filing deadlines are approaching. It may be true that Hillary Clinton has stumbled, but it's insurgent Vermont Sen. Bernie Sanders, not Biden, who's been the beneficiary of those foibles.

Only someone with the name identification and built-in political advantages like Biden's could even make such a late play, and if he did pull the trigger, he would be a formidable candidate. He's the last wild card on either side before the 2016 field is crystallized. And a superPAC backing him, Draft Biden, has staffedup in recent weeks with notable hires and close Biden allies.

Biden may give a more direct answer next week, when he will appear on one of Stephen Colbert's first Late Show episodes on CBS. The more relaxed, comedy setting may be one where Biden feels more comfortable and more free to be frank.

But Biden has already been pretty transparent already — and all signs so far point to him not getting in.